Video player with code sensor

ABSTRACT

A video player ( 100 ) including at least one sensor ( 112 ) for sensing coded data ( 202 ) on or in a substrate and for generating first data, a transmitter ( 188 ) for transmitting said first data or second data at least partially based on the first data to a computer system and a receiver ( 188 ) for receiving video data associated with an identity derived from the first data from the computer system and at least one display device ( 102 ) for outputting a visual display based at least partially on the video data.

FIELD OF INVENTION

The present invention relates to devices for receiving machine-readableinput and for outputting a human discernable output, usually in the formof audio or visual information. More particularly the invention relatesto an video player which may be used to scan or sense machine-readablecoded data on a surface and to output a still image, a video clip oraudio material, or both audio and visual material.

COPENDING APPLICATIONS

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications/granted patentsfiled by the applicant or assignee of the present invention with thepresent invention:

U.S. Pat. Nos. 6,530,339, 6,631,897, Ser. Nos. 09/722,174, 09/722,174,09/721,896, U.S. Pat. Nos. 7,064,851, 6,826,547, 6,741,871, 6,927,871,6,980,306, 6,965,439, 6,788,982, Ser. No. 09/722,141, U.S. Pat. Nos.6,788,293, 6,946,672, 7,091,960, 6,792,165, 7,105,753, Ser. No.09/721,862.

The disclosures of these co-pending applications are incorporated hereinby cross-reference.

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications fled by theapplicant or assignee of the present invention on 20 Oct. 2000:

Ser. No. 09/693,415, U.S. Pat. Nos. 7,110,126, 6,813,558, 6,965,454,6,847,883, 7,131,058, Ser. No. 09/693,690, U.S. Pat. Nos. 6,982,798,6,474,888, 6,627,870, 6,724,374, Ser. No. 09/693,514, U.S. Pat. Nos6,454,482, 6,808,330, 6,527,365, 6,474,773, 6,550,997.

The disclosures of these co-pending applications are incorporated hereinby cross-reference.

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications filed by theapplicant or assignee of the present invention on 15 Sep. 2000:

U.S. Pat. Nos. 6,679,420, 6,963,845, 6,995,859, 6,720,985.

The disclosure of these co-pending applications are incorporated hereinby cross-reference.

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications filed by theapplicant or assignee of the present invention on 30 Jun. 2000:

U.S. Pat. Nos. 6,824,044, 6,678,499, 6,976,220, 6,976,035, 6,766,942,Ser. No. 09/609,303, U.S. Pat. Nos. 6,922,779, 6,978,019, Ser. No.09/607,843, U.S. Pat. No. 6,959,298, 6,973,450, Ser. No. 09/609,553,U.S. Pat. No. 6,965,882, Ser. No. 09/608,022, U.S. Pat. Nos. 7,007,851,6,957,921, 6,457,883, 6,831,682, 6,977,751, 6,398,332, 6,394,573,6,662,923.

The disclosures of these co-pending applications are incorporated hereinby cross-reface.

Various methods, systems and apparatus relating to the present inventionare disclosed in the following co-pending applications filed by theapplicant or assignee of the present invention on 23 May 2000: U.S. Pat.Nos. 6,428,133, 6,526,658, 6,315,399, 6,338,548, 6,540,319, 6,328,431,6,328,425, 6,991,320, 6,383,833, 6,464,332, 6,390,591, 7,018,016,6,328,417, Ser. No. 09/575,197, U.S. Pat. No. 7,079,712, Ser. No.09/575,123, U.S. Pat. No. 6,825,945, Ser. No. 09/575,165, U.S. Pat. Nos.6,813,039, 6,987,506, 7,038,797, 6,980,318, 6,816,274, 7,102,772, Ser.No. 09/575,186, U.S. Pat. Nos. 6,681,045, 6,728,000, Ser. No.09/575,145, U.S. Pat. No. 7,088,459, Ser. No. 09/575,181, U.S. Pat. Nos.7,068,382, 7,062,651, 6,789,194, 6,789,191, 6,644,642, 6,502,614,6,622,999, 6,669,385, 6,549,935, 6,987,573, 6,727,996, 6,591,884,6,429,706, 6,760,119, Ser. No. 09/575,198, U.S. Pat. No. 6,290,349,6,428,155, 6,785,016, 6,870,966, 6,822,639, 6,737,591, 7,055,729, Ser.No. 09/575,129, U.S. Pat. Nos. 6,830,196, 6,832,717, 6,957,768, Ser.Nos. 09/575,162, 09/575,172, 09/575,170, U.S. Pat. Nos. 7,123,239,6,409,323, 6,281,912, 6,604,810, 6,318,920, 6,488,422, 6,795,215, Ser.No. 09/575,109, U.S. Pat. No. 6,859,289.

The disclosures of these co-pending applications are incorporated hereby cross-reference.

BACKGROUND

Purpose-specific devices such as televisions, video cassetteplayer/recorders and camcorders, as well as more general-purpose devicessuch as personal computers, can be used to play back video material suchas movies. Many of these devices can also be used to record videomaterial, such as home movies.

In general, these devices don't provide access to situated video, e.g.to a video clip associated with a concert poster encountered at a trainstation, or a demonstration video associated with a page in a workshopmanual. Each device must be used to seek out the desired video materialthrough a virtual space accessible through the device, or the videomaterial must be brought to the device in a device-compatible physicalformat.

The present invention utilizes methods, systems and devices related to asystem referred to as “netpage”, described in our co-pendingapplications listed above, wherein invisible coded data is disposed onvarious surfaces to render the surfaces interactive in the manner ofgraphical user interfaces to computer systems.

SUMMARY OF INVENTION

In one broad form the invention provides a hand-held video player withone or more sensors capable of sensing images including coded data.Images including coded data are sensed by the viewer and decoded. Thedecoded information is transmitted to a computer system which associatesthe decoded data with video data stored on the system, using previouslystored association data. The data is transmitted to the viewer and tothe user on a display screen.

Accordingly, in one broad form, the invention provides a video playerincluding:

at least one sensor for sensing coded data on or in a substrate and forgenerating first data;

a transmitter for transmitting said first data or second data at leastpartially based on the first data to a computer system;

a receiver for receiving video data associated with an identity derivedfrom the first data from the computer system;

at least one display device for outputting an visual display based atleast partially on the video data.

The player preferably includes a touch screen and the visual outputincludes interactive elements by which the user may modify the visualoutput by interaction with the touch screen.

The player may also include memory into which a file or files aredownloaded for subsequent viewing.

A video player according to one embodiment of the present invention is acompact device which, when used to click a video clip object orhyperlink on a page including machine readable code, plays back theassociated video clip. It contains a sensor for reading the machinereadable code, a transceiver for communicating with a base station, acompressed video and audio decoder, a color display, a displaycontroller, an audio digital-to-analog converter, a small audioamplifier, a speaker, a stereo headphone socket, a volume controlpotentiometer, and a controlling processor. It also typically containsplayback controls such as stop, play/pause, skip back, skip forward,although these may alternatively be provided in printed form on a codedsubstrate. Video clip information, such as title, chapter number,playing time, and pause status, is shown transiently on the colordisplay, superimposed on the video.

When the user touches the video player to a video clip object orhyperlink on a coded page, the player senses the page via its pagesensor, and decodes the link in the usual way via the base station. Itthen streams the video from the page network via the base station,subject to the user's interaction with the playback controls.

Audio is routed to the speaker, or, if a plug is present in the stereoheadphone socket, to the attached headphones or other external audiodevice. Audio may also be routed to wireless headphones via thetransceiver, either directly from the base station or via the player.

The video player may operate out-of-range of a netpage base station ifit is configured to utilize an embedded mobile telephone transceiver, orif it is itself embedded in a mobile telephone which it is configured tointeroperate with.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view from above of video player according to anembodiment of the invention;

FIG. 2 is a perspective view from below of the FIG. 1 player;

FIG. 3 is an exploded perspective view from above of the FIG. 1 player;

FIG. 4 is a side view from the rear of the player of FIG. 1;

FIG. 5 is a plan view from above of the FIG. 1 player;

FIG. 6 is a side view from the right of the FIG. 1 player;

FIG. 7 is a cross-sectional view taken along line AA of FIG. 5;

FIG. 8 is a perspective view from above of the internal components ofthe FIG. 1 player;

FIG. 9 is a perspective view from below of the internal components ofthe FIG. 1 player;

FIG. 10 is an exploded perspective view of the underside of the PCB ofthe FIG. 1 player;

FIG. 11 is a perspective view showing the FIG. 1 player in use on acoded substrate; and

FIG. 12 is a block diagram of the electronics of the player.

DETAILED DESCRIPTION OF PREFERRED AND OTHER EMBODIMENTS

Referring to the drawings, there is shown a display unit 100. Thedisplay unit has a color LCD screen 102, five control buttons 104, aspeaker 106, volume control 108, an audio out jack 110 and a infraredsensor device 112.

The body of the player is formed of upper and lower moldings 114 and 116respectively which encapsulate a PCB 118 and all of the electroniccomponents are mounted on or connected to this PCB. Power for the playeris supplied by a rechargeable 3 volt lithium ion battery 120. Thebattery is not user replaceable and is located within the body. The twomoldings 114 and 116 clip together at the upper edge 122 and are heldtogether by three screws 124 extending through apertures 126 in thelower molding to engage in threaded studs (not shown) in the uppermolding 114. The screws pass through holes 128 in the PCB and sandwichthe PBC between lower bosses 130 formed in the lower molding 116 and thestuds in the upper molding 114.

The LCD screen 102 is mounted on the top of the PCB and is preferably afull color thin film transistor type display, or a display havingsimilar or better contrast and switching speeds; such displays allowvideo to be played at acceptable qualities. The video player may includea touch screen overlay 132.

A combined data and power connector 134 is connected to the PCB and isaccessible via opening 136 in the body. The connector 134 includes apower input socket 138 for recharging of the battery 120 and a datasocket 140 for input/output of data to and from the player. Theconnector 134 is connected to the PCB via a flexible PCB 142 andconnectors 144 and 146.

The speaker 106 is also connected to the PCB at its lower edge viaconnector 148 and is positioned between the PCB and the lower edge ofthe body. The speaker may be hard wired to the PCB rather than beingprovided with a removable connector. The audio output is used to playaudio associated with the video, and optionally to provide operatingfeedback to the user.

The battery 120 is also positioned between the PCB and the lower edge ofthe body. A removable connector 150 is provided to connect the batteryto the PCB. However, since the battery is not intended to be userreplaceable, a permanent connection may be used. The battery ispreferably shaped to fit the body and accordingly has a beveled corner152.

The volume control 108 and audio out jack 110 are mounted directly onthe right hand side of the PCB and are accessible via openings 154 and156 respectively in the right hand side of the body.

The PCB also includes a compressed audio visual decoder 178, processorchip 180, dynamic RAM (DRAM) 182, flash or ROM 184, display controller250 for controlling the LCD, a transceiver chip 188 and an aerial 190.

Mounted on the lower surface of the PCB, at the top left hand corner, isthe sensor device 112 which is capable of detecting infrared markings ona substrate. The sensor device 112 comprises a LED 160 and an imagesensor 162. The image sensor 162 is sensitive to infrared light, eitherinherently or by use of filters and the LED 160 emits infrared light,again inherently or by use of filters. In use infrared light is emittedfrom the LED 160 and passed through an light guide 164 and then throughan aperture 166 in the body formed by the two casings 114 & 116. Lightpasses through the aperture 166, the optical molding 164 in the lowermolding. Light passes through the aperture 166, the optical molding 164and is focused onto the image sensor 162. The optical molding preferablyincludes a lens 168 and may include a beam splitter/combiner to allowlight from and to the LED and the image sensor to follow the same path.

The infrared LED 160 may be strobed in synchrony with image capture toprevent motion-blurring of captured tag images. The image sensortypically consists of a 200×200 pixel CMOS or CCD image sensor with anear-infrared bandpass filter.

The free end portion 170 of the light guide 164 is cylindrical and aforce sensor collar 172 is slideably mounted on the cylindrical portion.The collar extends beyond the free end of portion 170 so that when theplayer is pushed against the surface the collar rather than the lens 168contacts the surface. The collar has a limited amount of movement sothat when pressed against a surface there will be a small gap betweenthe surface and the lens 168. The lens 168 is designed to have thesurface in focus at most orientations of the player to the surface; itwill be appreciated that with different contact angles the distance willchange and so the depth of field of focus needs to encompass this range.

The collar 172 extends around and behind the sensor device 112 andengages a micro switch 174. The micro switch is biased to an openposition; pushing on the collar against the micro switch 174 overcomesthe biasing means in the switch 174 and closes it. When the force isremoved the biasing means urges the collar outward and opens the switchagain. A separate biasing means may be provided external of the switch174 in addition to the micro switch's own biasing means. The sensordevice is capable of detecting infrared absorptive tags, such as netpage tags. For a full description of the electronic processes involved,reference is made to our co-pending application U.S. Ser. No.09/721,893, now issued U.S. Pat. No. 6,792,165, referred to earlier. TheCCD 162, the LED 160 and processing functions incorporated in theprocessor chip 180 are similar to those disclosed in the co-pendingapplication.

The player is thus capable of sensing and decoding netpage tags on asubstrate. Image data captured by the CCD 162 is sent to the processorchip 180 and decoded to a region ID (or page ID) and a tag ID. Theregion ID and tag ID, together with other necessary information, istransmitted to the netpage system via the transceiver chip 188 andaerial 190. The netpage system resolves the region ID and tag ID tocorresponding document data which it transmits back to the player. Thisis received by the processor 180 via the transceiver. The renders thedata for display on the LCD 102 via the display controller 250.

Component digital video for standard-definition television (SDTV) issampled at 720 active luminance samples and 360 active chrominance (redand blue color difference) samples per line, with about 488 active linesper frame in 525/59.94 systems and 576 active lines per frame in 625/50systems. 525/59.94 systems have a frame rate of 29.97 Hz, correspondingto an interlaced field rate of 59.94 Hz, while 625/50 systems have aframe rate of 25 Hz, corresponding to an interlaced field rate of 50 Hz.With 8-bit sampling per component, i.e. 16 bits per pixel at theluminance sampling rate, both systems have a data rate of about 21Mbytes/s. This is somewhat lower than the data rate implied by the 13.5MHz luminance sample rate, since each line contains inactive samples andeach frame contains inactive lines. Component digital video for SDTV isknown as 4:2:2, in reference to the ratios of its luminance andchrominance sampling rates to a base frequency of 3.375 MHz.

In 4:2:0 video, chrominance is also subsampled by a factor of two withrespect to luminance in the vertical dimension, giving 12 bits per pixelat the luminance sampling rate, and a data rate of about 16 Mbytes/s.4:2:0 is commonly used in JPEG and MPEG compression, discussed below.

Video is also commonly sampled at, or subsampled to, 360 (352) luminancesamples per line and 240 lines per frame (in 525/59.94) or 288 lines perframe (in 625/50), particularly in low-rate versions of MPEG and relatedvideo compression standards, giving a data rate of about 4.8 Mbytes/s.The MPEG variant is referred to as SIF (Standard Interchange Format),while the International Telecommunications Union's videoconferencingvariant is referred to as CIF (Common Intermediate Format). Thesquare-pixel equivalent is normally taken to be 320×240.

For both storage and communications purposes, there is a strongimperative to compress a digital video stream. In the JPEG still imagecompression standard, blocks of an image are transformed into thefrequency domain via a discrete cosine transform (DCT). This has theeffect of concentrating image energy in relatively lower-frequencycoefficients, allowing higher-frequency coefficients to be more crudelyquantized, the principal source of compression in JPEG. At compressionratios at 10:1 and below, JPEG introduces negligible image degradation.In the MPEG video compression standard, periodic reference frames arecoded using a scheme similar to JPEG, to support random access.Remaining frames are coded using local block-based motion vectors, withreference to an earlier frame or to an earlier frame and a future frame.

The MPEG-1 compression standard, targeted at the 1.5 Mbit/s data rate ofcompact discs, is generally credited with achieving the same quality asVHS tapes at a bit rate of 1.2 Mbit/s, when operating at SIF resolutionat 30 Hz non-interlaced.

Digital audio is usually sampled at 44.1 kHz, i.e. at twice the 22.05kHz upper cutoff frequency of the 25th critical band of human hearing.Slightly higher sampling frequencies, such as 48 kHz, are sometimes usedbecause in reality it is impractical to lowpass filter the audio with asharp cutoff at 22.05 kHz prior to sampling. With typical quantizationof 16 bits per channel, a stereo signal therefore generates 1.41 Mbit/s,and this is consequently the data rate of many common digital audioapplications, including, for example, the audio compact disc (if errorcorrection overhead is ignored).

Because the typical 1.41 Mbit/s digital audio data rate is non-trivial,there is a strong incentive to also compress the digital audio signal.The most successful digital audio compression schemes have a perceptualbasis, i.e. they exploit the frequency-dependence of the threshold ofhuman hearing, and signal-dependent masking, whereby a relatively loudertone can locally raise the threshold curve and thus mask relativelysofter adjacent tones. Audio compression also typically relies ontraditional compression techniques such as entropy-coding. Inmulti-channel audio, inter-channel redundancy is also commonlyexploited.

The MPEG Audio Layer 3 (MP3) standard uses perceptual coding to achieve‘near-CD’ and ‘CD’ quality reproduction at compression ratios of between16:1 and 12: 1, i.e. reducing the data rate from 1.41 Mbit/s to between88 Kbit/s and 118 Kbit/s.

The player includes a dedicated compressed video and audio decoder 178which produces square-pixel progressive-scan digital video and digitalaudio output. For example, to handle MPEG-1 encoded video and audio, avideo and audio decoder similar to a C-Cube CL680 decoder may be used.To handle MPEG-2 encoded video and audio, a video and audio decodersimilar to C-Cube's ZiVA-3 decoder may be used. An MPEG-1 decodertypically uses a 4 Mbit DRAM during decoding, while an MPEG-2 decodertypically uses a 16 Mbit SRAM during decoding. The decoder memory 179may be dedicated to the decoder, or may be part of a memory 182 sharedwith the processor.

Any of a number of other video and audio encoding standards may besupported via suitable video and audio decoders, including RealNetworks'RealVideo.

Digital video decompressed by the decoder is displayed on the colordisplay 102 via a display controller 250.

Digital audio decompressed by the decoder is converted to analog via adigital-to-analog converter (DAC) 183, is amplified by an amplifier 185subject to the volume control, and is output to a speaker 106 or to anexternal audio device via an audio jack 110. The speaker 106 is disabledwhen the audio jack is in use.

The processor chip contains a processor unit 181 which controls andcoordinates the various electronic components of the player. Theprocessor unit 181 executes software which monitors, via the tag sensor162, the identity of the underlying page and the position of the playerrelative to the page; communicates the identity and position data to thenetpage base station via a wireless transceiver 188; receives video clipinformation and streaming audio data from the base station via thetransceiver 188; displays clip information to the status display 102;decompresses streaming audio data to the audio output via the audiodecoder 183; and interprets user input captured via the user interfacebuttons 104. The embedded software executed by the processor is storedin the non-volatile memory 184, typically in the form of ROM and/orflash memory. Identity information unique to the player, as well ascommunications encryption keys, are also stored in non-volatile memory.During execution the processor utilizes faster volatile memory,typically in the form of a 64 Mbit (8 Mbyte) dynamic RAM (DRAM).

Assuming a compressed video data rate of 1.2 Mbit/s (e.g. MPEG-1 SIF at30 Hz), the player's memory 182 can hold about one minute of compressedvideo (including stereo audio). With higher compression ratios or morememory, correspondingly longer clips can be held. If streaming playbackis used by the player, then only a small video buffer is required toeliminate transmission jitter, and a significantly smaller memory may beused.

The processor unit 181 communicates with the other components via ashared bus 187. The processor unit 181, the bus 187, and any number ofother components may be integrated into a single chip. As indicated inthe block diagram, the integrated components may include the digitaltransceiver controller 189, the video decoder interface 191, and the tagimage sensor interface 193. A parallel interface 195 is interposedbetween the bus 187 and the buttons 104, LED 160, touch sensor 132 andcontact switch 174 In a more highly integrated chip, they may alsoinclude the video decoder 178, the audio DAC 183, the tag image sensor162, and the memory 182. The analog radio transceiver 188 is unlikely tobe integrated in the same chip, but may be integrated in the samepackage.

Since the player incorporates a dedicated video/audio decoder 178, theprocessor unit 181 only needs to be powerful enough to control andcoordinate the other components. Alternatively, the video/audio decodermay be omitted, and a more powerful processor can used to decode thecompressed video and audio in software.

The transceiver 188 is typically a short-range radio transceiver. It maysupport any of a number of wireless transmission standards, includingBluetooth/IEEE 802.15, IEEE 802.11, HomeRF/SWAP, HIPERLAN, and OpenAir.Bluetooth/IEEE 802.15, IEEE 802.11-1997, HIPERLAN, OpenAir, andHomeRF/SWAP all support transmission rates in the range of 1 to 2Mbit/s. IEEE 802.11b supports transmission rates of 5.5 Mbit/s and 11Mbit/s. HIPERLAN also supports a transmission rate of 24 Mbit/s in analternative mode. Beyond these currently-supported wireless LAN (WLAN)standards, next-generation WLAN standards promise to supporttransmission rates of 100 Mbit/s and beyond.

The player may alternatively be connected to the base station by cable,or may utilize a non-radio-frequency wireless transport, such asinfrared. IEEE 802.11, for example, optionally utilizes an infraredtransport. IrDA also utilizes an infrared transport.

The player may alternatively or additionally contain a mobile telephonetransceiver for longer-range communication with a netpage server via amobile telephone network. If the transceiver supports a third-generation‘always-on’ packet-switched connection, then the player may download orstream audio content at will. If the transceiver only supports acircuit-switched connection, then the player may choose to connect (andpotentially stream audio content) only when it encounters a hyperlink.

If the player incorporates a longer-range transceiver, then it may actas a netpage base station for wireless netpage pens and other netpagesensing devices.

Assuming a compressed video data rate of 1.2 Mbit/s (e.g. MPEG-1 SIF at30 Hz), the receiver must support a data rate of at least 1.2 Mbit/s.This is within the capabilities of some of the wireless transmissionstandards described above. Lower (or higher) data rates can be readilyachieved by decreasing (or increasing) frame resolution, frame rateand/or image quality. The netpage network can dynamically recode acompressed video stream to match a particular player's capabilities, ifnecessary, either at a server or at a base station.

The player is controlled by five buttons, generally indicated by 104.The five buttons are a power button 192, a play button 194, a stopbutton 196, a rewind button 198 and a fast forward button 200. Thebuttons are sandwiched between the upper molding 114 and the PCB 118 andact on switches 202, 204, 206, 208 & 210 respectively.

The player is provided with a stand 212 comprising two legs 214 & 216hinged together at adjacent ends by a pin 218 engaging in alternatingsets of cylindrical apertures 220 & 222 in the two wings. The wing 214is mounted at its other end for rotation on the lower molding 116 byintegral pins 224. The wing 216 is mounted at its other end for rotationand sliding on the lower molding 116 by integral pins 226. The pins 226engage in slots 228 in downward extending rails 230. The slots are longenough to allow the two legs to be laid flat between the two rails. Therails extend from the general plane of the lower molding more than thethickness of the legs so that when folded flat the player rests on therails not the wings. The slots are not smooth but have a number ofprotrusions 232 which limit movement of the pins, so that the legs maybe placed in one of a number of positions to tilt the player relative tothe surface on which it rests.

Referring to FIG. 11, in use the user has one or more substrates 200having netpage tags 202 tiled over its surface. For clarity only some ofthe tags are shown. The substrate 200 may be paper, electronic papersuch as used by E-ink Corporation, a plastics sheet or any othersuitable substrate. The substrate carries one or more entries of humanreadable text 204, usually titles of one or more videos available forviewing by the user. The human readable text may optionally include asummary or a small logo or picture 224. The entries themselves may be“active” in that the user may select the entry by selecting the summaryor a separate selection “button” may be provided to select the video.The entire page may be tiled with netpage tags or tags may only beprovided in “active” areas. To select a video the user merely clicks thesensor device 112 on the relevant “active” area.

The sensor device 112 senses one or more of the tags 202, decodes thecoded information and transmits this decoded information to the netpagesystem. As discussed in our co-pending application U.S. Ser. No.09/722,142, now issued U.S. Pat. No. 6,965,439, each tag incorporatesdata which identifies the page it is on and its location within thepage. The netpage system is thus capable of determining what videofile(s) are associated with the sensed tags and so can extract videofile(s) and transmit them to the player for display on the LCD.

Data is preferably compressed in MPEG format and streamed to the player100. The data is received via the aerial 190 and transceiver 188 andpassed to the dedicated MPEG decoder 178 for decoding. The decoded datais then transferred to the display controller 250 for display on thecolor display 102. Streaming video is buffered in the player's DRAM 182to eliminate transmission jitter. The size of the required bufferdepends on wireless bandwidth contention and contention for the serversupplying the streaming data.

Control of the video playback is via the control buttons 104. When theuser presses one of the buttons, the processor 180 determines thefunction of the button and sends an appropriate instruction to thenetpage system. According to the instruction, the system modifies orstops transmission of data to the player.

After a video clip has been selected but before playback has commencedthe display may change to display the title and optionally the playingtime of the video. Optionally controls such as play, fast forward,rewind stop and pause may be displayed, such that the user may controlthe player via the screen rather than the dedicated control buttons.

The video player optionally includes a microphone, video camera and arecord button. It can then be used to record audio and/or video input ,thus providing another kind of netpage input. Recorded input may, forexample, be associated with a location on a netpage, in the form of anannotation, by clicking at the location with the video player.Subsequent clicks at the same location using a video player then causethe audio and/or video annotation to be played back. If the surfaces ofphysical objects are universally netpage-enabled, i.e. tagged withunique netpage tags, then audio and/or video annotations can be placedalmost anywhere. Such audio and video annotations may be private orpublic. When they are private they may only be played back by theirauthor. When they are public they may be played back by anyone.

When incorporating a microphone and video camera, the video player canbe configured to act as a wireless telephone or video telephone underthe control of a telephony application. Since the player lacks a userinterface for dialing numbers, numbers can be selected from a netpage inthe manner described in our co-pending application U.S. Ser. No. 09/721895.

A video clip may be associated with a netpage in the form of ahyperlink, in which case activation of the hyperlink by the video playeris ultimately handled by an application whose responsibility it becomesto provide the video clip to the player. A video clip may also belogically embedded as a video clip object in a page description, inwhich case clip activation is ultimately handled by the page serverwhich holds the page description. Any click in the zone of the videoclip object is interpreted by the page server as video clip activation.In either case the actual video clip may be stored on a separate remoteserver, which may become involved in the streaming playback or downloadof the video clip.

The video player can download a video clip activated by the user intoits internal memory before making it available for playback, or it canstream the video clip on demand from the remote server in response tothe user interacting with the player's playback controls. The player mayalso include non-volatile storage, such as flash memory, magnetic disk,CD writer or CD rewriter for storage of downloaded video data. Theschemes outlined in our co-pending application U.S. Ser. No. 09/722,087,now issued U.S. Pat. No. 6,788,982, regarding storage of downloaded dataand device identity may be used for storage of video data.

The player typically incorporates power management. After a period ofinactivity the player may inactivate the status display. After a longerperiod of inactivity the processor may enter a power-conservingquiescent state. Power management may be coupled with the tag sensormicro switch, allowing wake-up on page interaction. The player may alsoincorporate an accelerometer for this purpose.

Whilst the invention has been described with reference to the netpagesystem which uses invisible tags, the invention is not limited to thenetpage system or the use of invisible tags. If desired, the inventionmay utilize tags or codes which are visible to the average unaided humaneye, such as bar codes. The tags need not merely encode an identitywhich is then used to look up the relevant files. The tags may encodeinstructions at a higher level. For example a tag may encode aninstruction of “play chapter 99”. If invisible tags are used they neednot be limited to the tags disclosed in relation to the netpage system.Other tagging systems are available and any suitable tagging system maybe used. The invention is not limited to the use of inks which absorbcertain wavelengths or fluoresce certain wavelengths. Magnetic inks,surface modification, including apertures, modification of the structureof the substrate itself all fall within the scope of the invention. Thesystems and methods to link the audio player of the present inventionand the source of the audio files are not limited to netpage systems. Avideo player may be linked by a cable to a single computer, rather thana network of computers.

The present invention has been described with reference to a preferredembodiment and number of specific alternative embodiments. However, itwill be appreciated by those skilled in the relevant fields that anumber of other embodiments, differing from those specificallydescribed, will also fall within the spirit and scope of the presentinvention. Accordingly, it will be understood that the invention is notintended to be limited to the specific embodiments described in thepresent specification, including documents incorporated bycross-reference as appropriate. The scope of the invention is onlylimited by the attached claims.

1. A video player including: a body; at least one sensor positioned in the body so that coded data printed on a substrate is sensed by positioning the video player body relative to the substrate, the sensor generating first data from the sensed coded data; a transmitter positioned in the body for transmitting, to a computer system, said first data or second data at least partially based on the first data; a receiver positioned in the body for receiving, from the computer system, video data associated with an identity derived from the first data; and at least one display device positioned in the body for outputting a visual display based at least partially on the video data.
 2. The video player of claim 1 further including a memory for storing received video data.
 3. The video player of claim 2 wherein at least part of the memory is user replaceable.
 4. The video player of claim 2 wherein the video player has an identity and further includes processor means to store the identity or data indicative of the identity with or in any file stored in memory.
 5. The video player of claim 1 further including a means to display information relating to received video data.
 6. The video player of claim 1 including an actuator to enable a user to activate the at least one sensor.
 7. The video player of claim 6, wherein the actuator is a force sensor.
 8. The video player of claim 1 including a motion sensor to enable a user to actuate the video device.
 9. A method of obtaining video data, the method including: providing a plurality of separately identifiable video data; associating each of the plurality of separately identifiable video data with one or more identities; providing at least one paper-like substrate having at least one selection data printed thereon, the at least one selection data associated with or encoding at least one identity; selecting at least one of the at least one selection data of the at least one paper-like substrate with a selection device locate in a video player body, the selection device being located in the video player body so as to perform said selecting by positioning the video player body relative to the paper-like substrate; determining the identity or identities associated with the selected selection data and identifying the file or files associated with the identity or identities determined from the selection data; and downloading the video data identified to the selection device to the video player.
 10. The method of claim 9 wherein the selection data includes machine readable codes.
 11. The method of claim 9 further including playing the video data.
 12. The method of claim 9 further including storing the video data in a memory of the selection device.
 13. The method of claim 9 wherein the selection device has a unique identity.
 14. The method of claim 9 wherein the selection device has a unique identity and further including storing the video data in memory of the selection device together with association data indicative of an association between the identity of the selection device and the video data.
 15. The method of claim 9 further including: selecting video data stored in memory of the selection device; extracting from the memory the identity of the selection device associated with the selected video data; comparing the extracted identity with the identity of the selection device; and if the extracted identity and the identity of the selection device are the same, playing the file.
 16. The method of claim 9 further including: selecting video data stored in memory of the selection device; extracting from the memory the identity of the selection device associated with the selected video data; comparing the extracted identity with the identity of the selection device; and if the extracted identity and the identity of the selection device are not the same, not playing the file.
 17. The method of claim 9 wherein the selection data is invisible or substantially invisible to the average unaided human eye.
 18. The method of claim 9 wherein the substrate has visible data associated with at least one selection data. 